A method of operating a power tool detects human contact with a non-moving implement in the power tool. The method includes generating a series of samples of an electrical signal passing through the non-moving implement, identifying a component for each sample in the series of samples of the electrical signal, identifying a first maxmin value corresponding to a first plurality of samples in the series of samples occurring during a first periodic time interval with reference to a difference between a maximum value and a minimum value identified in the components of the first plurality of samples, and identifying human contact with the non-moving implement in response to the first maxmin value being greater than a first predetermined threshold.

The disclosure relates to a machine tool device, in particular a handheld machine tool device, comprising at least one control and/or regulating unit and at least one drive unit sensor unit for detecting at least one drive unit parameter that can be processed at least in order to control and/or regulate a drive unit of a machine tool and/or in order to output information to an operator of the control and/or regulating unit. According to the disclosure, the machine tool device comprises at least one operator sensor unit in order to detect at least one operator-specific parameter that can be processed at least in order to control and/or regulate the drive unit and/or in order to output information to an operator of the control and/or regulating unit.

A safety system for a power miter saw comprises a support member, at least one multidirectional manipulator including a workpiece holder member moveably mounted to the support member for securing a workpiece in place, and a control box. The workpiece holder member includes a presence indicator operatively connected to the control box and configured to detect the physical presence of a saw operator's hand on the at least one multidirectional manipulator when the saw operator's hand engages the presence indicator. The control box is operatively connectable to a trigger switch of the power miter saw so that an electric motor of the power miter saw is activated only when both the presence indicator of the safety system and the trigger switch of the power miter saw are engaged by both hands of an operator of the power miter saw.

A power tool and methods are provided for detecting objects (e.g., flesh or other materials) in the operating path of a power tool's output component (e.g., saw blade or drill bit). An object detection sensor in the power tool generates an output signal indicative of a type of material detected in the operating path of the power tool. A power tool controller receives the object detection sensor output and determines when a material in the operating path of the power tool changes. The controller changes operation of a motor of the power tool (e.g., increasing or decreasing speed or stopping the motor) in response to the detected material change. The object detection sensor may include, for example, an RF sensor, a capacitive sensor, a camera, a conductivity probe, or an ultrasound probe.